I've just finished runnig benchies again with the Catalyst 8.3 hotfix. Under "information center" in the CCC, it shows the Catalyst Version as 8.4. I've been logging benchmark results over the past few days, so I have an easy comparison.
Crysis CPU Benchmark
1920x1200, High Detail, No AA
8.3 --> 26.745
8.4 --> 26.8
3DMark06 Pro V 1.1
1920x1200, No AA, No AF
Average over 4 passes
8.3 --> 15,187
8.4 --> 15,179
I even loaded up a save game of The Witcher because it has lots of laggies while running around heavily populated towns. I noticed no difference in performance.
With the Crysis benchmark, at the point where you shoot the pickup truck, a massive graphic anomoly manifestid itself in the form of a green and black wall. This happened in all 4 passes of the test.
I will be un-installing 8.4 and going back to 8.3 because of the Crysis graphic issue.